CoreSight doesn't allocate thread structure for unknown_thread in etm
auxtrace, so unknown_thread is NULL pointer. If the perf data doesn't
contain valid tid and then cs_etm__mem_access() uses unknown_thread
instead as thread handler, this results in segmentation fault when
thread__find_addr_map() accesses thread handler.
This commit creates new thread data which is used by unknown_thread, so
CoreSight tracing can roll back to use unknown_thread if perf data
doesn't include valid thread info. This commit also releases thread
data for initialization failure case and for normal auxtrace free flow.
Signed-off-by: Leo Yan <[email protected]>
---
tools/perf/util/cs-etm.c | 25 +++++++++++++++++++++++--
1 file changed, 23 insertions(+), 2 deletions(-)
diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 6533b1a..417302c 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -239,6 +239,7 @@ static void cs_etm__free(struct perf_session *session)
for (i = 0; i < aux->num_cpu; i++)
zfree(&aux->metadata[i]);
+ thread__zput(aux->unknown_thread);
zfree(&aux->metadata);
zfree(&aux);
}
@@ -266,6 +267,7 @@ static u32 cs_etm__mem_access(struct cs_etm_queue *etmq, u64 address,
if (!thread) {
if (cpumode != PERF_RECORD_MISC_KERNEL)
return -EINVAL;
+
thread = etmq->etm->unknown_thread;
}
@@ -1355,6 +1357,23 @@ int cs_etm__process_auxtrace_info(union perf_event *event,
etm->auxtrace.free = cs_etm__free;
session->auxtrace = &etm->auxtrace;
+ etm->unknown_thread = thread__new(999999999, 999999999);
+ if (!etm->unknown_thread)
+ goto err_free_queues;
+
+ /*
+ * Initialize list node so that at thread__zput() we can avoid
+ * segmentation fault at list_del_init().
+ */
+ INIT_LIST_HEAD(&etm->unknown_thread->node);
+
+ err = thread__set_comm(etm->unknown_thread, "unknown", 0);
+ if (err)
+ goto err_delete_thread;
+
+ if (thread__init_map_groups(etm->unknown_thread, etm->machine))
+ goto err_delete_thread;
+
if (dump_trace) {
cs_etm__print_auxtrace_info(auxtrace_info->priv, num_cpu);
return 0;
@@ -1369,16 +1388,18 @@ int cs_etm__process_auxtrace_info(union perf_event *event,
err = cs_etm__synth_events(etm, session);
if (err)
- goto err_free_queues;
+ goto err_delete_thread;
err = auxtrace_queues__process_index(&etm->queues, session);
if (err)
- goto err_free_queues;
+ goto err_delete_thread;
etm->data_queued = etm->queues.populated;
return 0;
+err_delete_thread:
+ thread__zput(etm->unknown_thread);
err_free_queues:
auxtrace_queues__free(&etm->queues);
session->auxtrace = NULL;
--
2.7.4
There have two spaces ahead function name cs_etm__set_pid_tid_cpu(), so
remove one space and correct indentation.
Signed-off-by: Leo Yan <[email protected]>
---
tools/perf/util/cs-etm.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 417302c..3137fbe 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -612,8 +612,8 @@ cs_etm__get_trace(struct cs_etm_buffer *buff, struct cs_etm_queue *etmq)
return buff->len;
}
-static void cs_etm__set_pid_tid_cpu(struct cs_etm_auxtrace *etm,
- struct auxtrace_queue *queue)
+static void cs_etm__set_pid_tid_cpu(struct cs_etm_auxtrace *etm,
+ struct auxtrace_queue *queue)
{
struct cs_etm_queue *etmq = queue->priv;
--
2.7.4
On 3 May 2018 at 09:18, Leo Yan <[email protected]> wrote:
> There have two spaces ahead function name cs_etm__set_pid_tid_cpu(), so
> remove one space and correct indentation.
>
> Signed-off-by: Leo Yan <[email protected]>
Acked-by: Mathieu Poirier <[email protected]>
> ---
> tools/perf/util/cs-etm.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
> index 417302c..3137fbe 100644
> --- a/tools/perf/util/cs-etm.c
> +++ b/tools/perf/util/cs-etm.c
> @@ -612,8 +612,8 @@ cs_etm__get_trace(struct cs_etm_buffer *buff, struct cs_etm_queue *etmq)
> return buff->len;
> }
>
> -static void cs_etm__set_pid_tid_cpu(struct cs_etm_auxtrace *etm,
> - struct auxtrace_queue *queue)
> +static void cs_etm__set_pid_tid_cpu(struct cs_etm_auxtrace *etm,
> + struct auxtrace_queue *queue)
> {
> struct cs_etm_queue *etmq = queue->priv;
>
> --
> 2.7.4
>
On 3 May 2018 at 09:18, Leo Yan <[email protected]> wrote:
> CoreSight doesn't allocate thread structure for unknown_thread in etm
> auxtrace, so unknown_thread is NULL pointer. If the perf data doesn't
> contain valid tid and then cs_etm__mem_access() uses unknown_thread
> instead as thread handler, this results in segmentation fault when
> thread__find_addr_map() accesses thread handler.
>
> This commit creates new thread data which is used by unknown_thread, so
> CoreSight tracing can roll back to use unknown_thread if perf data
> doesn't include valid thread info. This commit also releases thread
> data for initialization failure case and for normal auxtrace free flow.
>
> Signed-off-by: Leo Yan <[email protected]>
> ---
> tools/perf/util/cs-etm.c | 25 +++++++++++++++++++++++--
> 1 file changed, 23 insertions(+), 2 deletions(-)
>
> diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
> index 6533b1a..417302c 100644
> --- a/tools/perf/util/cs-etm.c
> +++ b/tools/perf/util/cs-etm.c
> @@ -239,6 +239,7 @@ static void cs_etm__free(struct perf_session *session)
> for (i = 0; i < aux->num_cpu; i++)
> zfree(&aux->metadata[i]);
>
> + thread__zput(aux->unknown_thread);
> zfree(&aux->metadata);
> zfree(&aux);
> }
> @@ -266,6 +267,7 @@ static u32 cs_etm__mem_access(struct cs_etm_queue *etmq, u64 address,
> if (!thread) {
> if (cpumode != PERF_RECORD_MISC_KERNEL)
> return -EINVAL;
> +
Extra line, please remove.
With this change:
Acked-by: Mathieu Poirier <[email protected]>
> thread = etmq->etm->unknown_thread;
> }
>
> @@ -1355,6 +1357,23 @@ int cs_etm__process_auxtrace_info(union perf_event *event,
> etm->auxtrace.free = cs_etm__free;
> session->auxtrace = &etm->auxtrace;
>
> + etm->unknown_thread = thread__new(999999999, 999999999);
> + if (!etm->unknown_thread)
> + goto err_free_queues;
> +
> + /*
> + * Initialize list node so that at thread__zput() we can avoid
> + * segmentation fault at list_del_init().
> + */
> + INIT_LIST_HEAD(&etm->unknown_thread->node);
> +
> + err = thread__set_comm(etm->unknown_thread, "unknown", 0);
> + if (err)
> + goto err_delete_thread;
> +
> + if (thread__init_map_groups(etm->unknown_thread, etm->machine))
> + goto err_delete_thread;
> +
> if (dump_trace) {
> cs_etm__print_auxtrace_info(auxtrace_info->priv, num_cpu);
> return 0;
> @@ -1369,16 +1388,18 @@ int cs_etm__process_auxtrace_info(union perf_event *event,
>
> err = cs_etm__synth_events(etm, session);
> if (err)
> - goto err_free_queues;
> + goto err_delete_thread;
>
> err = auxtrace_queues__process_index(&etm->queues, session);
> if (err)
> - goto err_free_queues;
> + goto err_delete_thread;
>
> etm->data_queued = etm->queues.populated;
>
> return 0;
>
> +err_delete_thread:
> + thread__zput(etm->unknown_thread);
> err_free_queues:
> auxtrace_queues__free(&etm->queues);
> session->auxtrace = NULL;
> --
> 2.7.4
>
On Tue, May 08, 2018 at 11:01:30AM -0600, Mathieu Poirier wrote:
> On 3 May 2018 at 09:18, Leo Yan <[email protected]> wrote:
> > CoreSight doesn't allocate thread structure for unknown_thread in etm
> > auxtrace, so unknown_thread is NULL pointer. If the perf data doesn't
> > contain valid tid and then cs_etm__mem_access() uses unknown_thread
> > instead as thread handler, this results in segmentation fault when
> > thread__find_addr_map() accesses thread handler.
> >
> > This commit creates new thread data which is used by unknown_thread, so
> > CoreSight tracing can roll back to use unknown_thread if perf data
> > doesn't include valid thread info. This commit also releases thread
> > data for initialization failure case and for normal auxtrace free flow.
> >
> > Signed-off-by: Leo Yan <[email protected]>
> > ---
> > tools/perf/util/cs-etm.c | 25 +++++++++++++++++++++++--
> > 1 file changed, 23 insertions(+), 2 deletions(-)
> >
> > diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
> > index 6533b1a..417302c 100644
> > --- a/tools/perf/util/cs-etm.c
> > +++ b/tools/perf/util/cs-etm.c
> > @@ -239,6 +239,7 @@ static void cs_etm__free(struct perf_session *session)
> > for (i = 0; i < aux->num_cpu; i++)
> > zfree(&aux->metadata[i]);
> >
> > + thread__zput(aux->unknown_thread);
> > zfree(&aux->metadata);
> > zfree(&aux);
> > }
> > @@ -266,6 +267,7 @@ static u32 cs_etm__mem_access(struct cs_etm_queue *etmq, u64 address,
> > if (!thread) {
> > if (cpumode != PERF_RECORD_MISC_KERNEL)
> > return -EINVAL;
> > +
>
> Extra line, please remove.
>
> With this change:
>
> Acked-by: Mathieu Poirier <[email protected]>
Thanks for reviewing, Mathieu. Will spin new patches and send out.
[...]
Thanks,
Leo Yan